Internal-combustion engine



Sept. 20, 1927.

E. T. LARKIN INTERNAL COMBUSTION ENGINE Original Filed Feb. 17. 1926 U\ m N\ Q R @w w n Q \QNM: 3% QN v \R h fl w \R v l I. N H \x a NP r t \N N N \N M m a Patented Sept. 20, 1927.

'UNITED' STATES j PATENT OFFICE.

ELWOGD T. LARKTN, F BUFFALO, NEW YORK, ASSIGNOR TO CHARLES A. CRIQUI, OiF

BUFFALO, NEW YORK.

NTERNAL CO'MBUSTION ENGINE.

Application filedFebruary 17, 1926, Serial No. 88,819. Renewed August 6,1927.

ing removable cylinder heads;

The objects of this invention are to con:

struct an engine of this kind in which the valves are arranged in the cylinder heads,

, so that the cylinder heads areremovable'im dividually in small units which can be readily handled: also to so construct the engine thatthe cylinder heads can be individually removed without disturbing the timing of the valves; also to'so construct the engine that the cylinder heads can be removed without disturbing any of the large parts ofthe engine or the intake or exhaust manifolds; also to provide cylinder heads of this kind which can be easily machined and constructed, and which may, if desired, be made of different material from the cylinder casting of the enginej also to provide means of improved construction for forn'iing tight joints between the several parts of the cylinder heads and the cylinder member I or casting; also to providl-i means of in'iproved constrnction for cooling the cylinder heads; also to improve the construct-ion of engines of this kind in other respects hereinafter specified. v

In the accompanying drawings.

1 is a transverse, sectional elevation of the upper part of an internal combustion engine and a removable cylinder head embodying my invention, the section being taken on line 1-l, Fig. 0.

Fig. 2 is an elevation thereof partly in section on line i2 2, Fig. 3. 7

Fl 3 is a top plan View thereof partly in section, taken along line 33, Fig. Figs is an enlarged, fragmentary, sec-- tionail view thereof on line 4l l, Fig. 2.

Fig. 5 is a fragmentary, sectional elevation thereof on line 55, Fig. 4:.

Fig. (l is a fragmentary, transverse, sectional elevation thereof similar to Fig. l but showing a modified construction. I

The engine to which my invention is applied may have any desired number of cylinders in which pistons 11 may recipmate. the cylinders being cooled by water jackets 12 formed around the same in any suitable manner. The cylinders 10 and the water jackets 12 preferably form a part of a cylinder member, casting or castings, and the cylinder member has portions which extend upwardly above the cylinders themselves and thus form a. plurality of inlet passages 15, one being'provided for each cylinder, which passages are arranged at one side of the engine and are connected to any suitable or desired inlet manifold 16. At the other side of the engine casting are provided a similar series of exhaust passages 17 connecting with an exhaust manifold 18. The cylinders may be provided with the usual cylindersleeves, (not shown), or the pistons may bear directly'onintegral parts of the cylinder casting or member, as indicated in. the drawings. The upper poi" tionof the cylinder casting or member is provided with a head chamber or substantially cylindrical bore for eachcylinder and arranged substantially concentric therewith, the head chambers being. in the construction shown, of greater diameterthan the cylinders themselves and having cylindrical walls 21 which terminate at their lower ends in shoulders 20 extending between the cylindrical walls 21 of the head chambers and thef the lower ends of the cylinder heads are adapted to seatagainst the shoulders 200T the cylinder casting. A suitable ring shaped gasket 24 is preferably provided be tween the lower extremities of the cylinder heads and the shoulders 20 of the'cylinder casting to form an air tight joint. Each cylinder head is provided with a transverse partition or web 25 which constitutes thetop of the compression chamber of the cylinder, and which is provided with the usual valve port-s controlled by inlet and exhaust valves,.the cylinder heads shown being provided with two inlet ports controlled by it pair of valves 27, and a. pair of exhaust ports controlled by a. pair of exhaust alves 28. The valve seats are formed on the bottom faces of the transverse web or wall 25 of the cylinder heads and the stems of thesevalves extend upwardly through #bearings 30 formed in water cooled portions ofpthe cylinder heads. Theyalves are held in their seated positions by means of the usual compression spring 31, Fig. 1.

The cylinder heads are provided at their upper portions with outwardly extending flanges 38 which are adapted to overlie the upper face of the cylinder member of the engine, and the usual studs or bolts may be used to clamp the cylinder heads in their positions in the cylinder casting so as to compress the gasket 24, but preferably the following construction is used. Adjacent to each flange 33 are provided a plurality of studs 35 suitably secured in the top face of the cylinder casting, and each stud 35 is provided with a clamp bar 36 provided with a hole through which the stud extends and the opposite ends of the clamp bars en- ,gag'e the flanges of two adjacent cylinders.

Consequently when nuts 37 cooperating with the studs 35 are screwed down against the clamp bars 86, each of these bars will press down upon the flanges of two adjacent cylinder heads. This construction is desirable for the reason that it makes it possible to use a smaller number of studs 35 of relatively large size, and consequently there is less chance of breaking, bending or damaging these studs during the shipment or handling of the engine. It will, of course, be understood that the studs 35 can be replaced by bolts fitting into threaded holes in the top of the cylinder casting.

Each cylinder head is provided with an inlet passage 40. leading to the inlet port or ports in the cylinder head and arranged to register with an inlet passage 15 of the cylinder member or casting, so as to form a substantially continuous passage from the inlet manifold 16 to the valve or valves 27 The other side of the cylinder head is provided with a similar passage 41 leading to the exhaust'valve or valves 28 and registering with the exhaust passage 17 of the cylinder member, seeparticularly Figs. 1, 3 and 4. The inlet and exhaust passages 40 and 41 in the cylinder heads are preferably separated by water spaces 42 which are separated by walls or partitions 43 and 44 from the inlet and exhaust passages 40 and 41 respectively, these walls being irregular in shape and extending around the inlet and exhaust passages and forming between adjacent pairs of inlet and exhaust valves, cavities or spaces 45 and 46 into which water may enter to cool as much as possible of the horizontal partition walls or webs 25 of the cylinder heads The lower portions of the walls 43 and 44 join the horizontal wall 25 around the valve seats.

Ignition of the charges of explosive gases in the cylinders is effected by means of spark plugs 48 which in the construction shown extend through apertures or recessedportions in the water jacketed cylinder walls of the engine cylinder member or casting, and are secured in suitably threaded holes in the lower flange of each cylinder head, below the lower horizontal wall 25 of. each head, as is clearly shown in Figs. 1 and 8; When this arrangement of the spark plugs is used annular sealing rings 50 are preferably employed between the cylindrical walls of the cylinder heads and the cylindrical walls 21 of the cylinder member, above the apertures '49 through which the spark plugs extend, these sealing rings being of any suitable or usual construction. I 4

In order to facilitate the machining of these cylinder heads, the cylindrical walls of the cylinder heads are preferably spaced at a distance from the cylindrical walls 21 in the upper portion of the cylinder member so that considerable clearance is formed between these telescoping cylindrical walls, as is clearly shown in Fig. 4. In order to prevent the explosive gases passing to a cylinder from mixing with the discharged products of combustion through this clearance space between the cylindrical walls, upright sealing plates or strips 51 are preferably employed which extend from the sealing ring 50 upwardly to the outwardly extending flanges 33 of the cylinder heads. These sealing plates may be made of any suitableresilient material and are preferably so formed that the middle portion thereof will press against the outer cylindrical face of a cylinder head and the edge portions thereof will yieldingly press against the corresponding face 21 of the cylinder casting, so that these plates or strips are under spring tension and therefore form tight joints with the adjacent cylindrical walls. By means of this construction the machining of the'cylinder heads and the cylindrical parts of the cylinder member with which they cooperate is reduced to a minimum since it is only necessary to accurately machine the lower edges of the cylinder heads which cooperate with the shoulders 20 of the cylinder casting, and the u11- der faces of the top flanges which fit against the upper surface of the cylinder casting.

Since the lower wall or partition 25 of each cylinder head is subjected to the highest temperatures of the engine, it is desirable to provide reliable means for efiiciently cooling this portion of each cylinder head, and for this purpose the following construction is preferably provided. An inlet or supply manifold or passage 55 for the cooling liquid, extending lengthwise of the engine and preferably formed integral with the engine cylinder casting, is connected directly with an inlet pipe 56 for the cooling liquid. G001- ing liquid is taken from this supply passage 55 to the cylinder heads by means ofaseries of siphon pipes 57, one being supplied for each cylinder head. These siphon pipes pass upwardly from the passage 55 through port1ons 58 of the water acke't of the upper part of the cylinder member, and watertight connections may be formed at the upper wall of the water jacketed space 58 by any suitable means such for example as gland or packing nuts 59 and 60. The "siphon tube 57 is bent above the upper end of the cylinder head and extends downwardly into the cylinder head, preferably to the lower portion thereof adj acent to the horizontal wall of the cylinder head which forms the top of the combustion space of the cylinder. The advantage of using a siphon tube is that in addition to distributing the coldest liquid where the greatest heat is to be dissipated, the arm of the siphon tube extending into the cooling liquid passage is lon er than the arm extending into the cylinderhead, so that when the water is drained from the engine jackets, the

: siphon tubes will drain practically all of the water out of the cylinder heads. When the cylinder heads are removed it is only necessary to loosen the gland nuts whereupon the siphon tube 57 may be lifted bodily with the cylinder head. If desired, the siphon tube can be made in two pieces connected at the gland nuts'59 and 60, but a single piece construction is preferred since this eliminates the possibility of breaking the siphon by means of an air leak.

The water may be discharged from the cylinder heads by means of any suitable pipes 62, which asshow'n are preferably of inverted 'U-shape and connect the upper part of the Water acketed portion of the cylinder head with the water jacketed part 58 of the engine cylinder casting.

The valves of the engine may, of course, be actuated in any suitable or desired manner and in the construction shown in Figs.

1 to 5, a single cam shaft 63 is provided which is suitably journalled in the upper portion of the cylinder casting and which is provided with a plurality of cams 64 adapted to engage cam levers 65 pivoted on suitable upwardly extending brackets 66 formed on the cylinder head. These levers engage bridge or connecting members '67 which con nect the opposite ends of a pair of valves, and each connecting member is provided with an upright guide stem 68 guided in upright cylindrical holes or recesses 69 in the cylinder heads. The guide stems 68 of the cross or connecting bars 67 insure an equal depression of the two valve stems actuated by each of the cam levers 65. Preferablyt-he upper portion of the cylinder casting is provided underneath the cam shaft 63 with a depression or oil reservoir 70 into which the cams 64 dip during the rotation thereof and thus insure a continuous lubrication of the cams and cam shaft bearings.

In the modified construction shown in Fig: 6 a pair ofcam shafts 71, 71 are pro vided at opposite sides of the cylinder heads. These cam shafts are provided with the usual cams acting on levers 72 and 7 3 which in turn acton the inlet and exhaust valves respectively. In this case also the two cam shafts are arranged above oil troughs 7 4 and 75 respectively, formed in the top portions of the cylinder casting and above water jacketed portions thereof. so that the cams are lubricated at each revolution of the shaft.-

.By means of the construction shown anycylinder head may be removed independently of the other cylinder heads by removing the spark plugs, releasing the connections of. the tubes 57 and 62 with the water jacket of the engine casting, and loosening the nuts on the studs 35, whereupon the cylinder head can be readily-removed by lifting the same vertically.

der head without disturbing the other cylinder heads, and also that if all cylinder heads. are to be removed, it is much easier to remove the heads individually than it is to re- 4 or exhaust manifolds of the engine need be removed in order to remove one or more cylinder heads. Consequently the removal of a cylinder head s not only facilitated in as much as the weight to be lifted is greatly reduced, but also a great deal of time is saved in the removal and replacing of the cylinder heads since no large parts of the engine need be disturbed and also the timing need not be disturbed. Furthermore, if desired, the cylinder heads may be made of different material from the cylinder member or casting. Furthermore each head of itself being small is more readily machined than a large casting including a plurality of heads, and the individual cylinder heads can alsobe more readily and less eX-pensively cast. The cooling arrangement described is particularly desirable since the cooling liquid is first used in the head where the greatest heat is to be dissipated. and is then conducted to the upper portion 58 of the water jacket, which portion is a continuation of and part of the water jacket 12 surrounding the cylinders 10.

I claim as my invention 1. A multi-cylinder internal combustion engine having a cylinder member provided with a plurality of'cylinders and having a cylindrical head chamber arranged above each cylinder, a cylinder head arranged in each of said head chambers and clamping means for securing said cylinder heads in said head chambers, including clamping bars engaging two adjacent cylinder heads, and means connected with the cylinder member for pressing said clamping bars against said cylinder heads.

2. A multi-cylinde'r internal combustion The construction-- described has the advantages, therefore, of making It possible to remove a single cylin- III engine having a cylinder member provided with a plurality of cylinders and having a cylindrical head chamber arranged above each cylinder, a cylinder. head arranged in each of said head chambers and clamping means for securing said cylinder heads in said head chan'ibers, including clamping bars engaging two adjacent cylinder heads, and screwthreaded members cooperating with said cylinder member for securing said clamping bars against said cylinder heads.

3. A multi-cylinder internal combustion engine having a cylinder member provided with a plurality of cylinders and having a cylindrical head chamber arranged above each cylinder and substantially concentric therewith, said head chambers being of larger diameter than said cylinders and forming annular shoulders with said cylinders, a cylinder head arranged in each-oi said head chambers and having a part adapted to seat on said shoulder, a flange adapted to overlap the, upper end of its cylinder chamber, clamping bars engaging the flanges of adjacent cylinder heads, studs secured to said cylinder member and extending through openings in said clamping bars, and nuts adapted to engage said studs to press said clamping. bars against said flanges to hold said cylinder heads in said chambers. 7

LA multi-cylinder internal combustion engine having a cylinder member including cylinders and substantially cylindrical head chambers arranged above each of said cylinders, cylinder heads adapted to be secured in said head chambers and having outer cylindrical walls spaced from the inner walls of said head chambers, and provided with valves, inlet and exhaust passages in said heads communicating with said valves, inlet and exhaust passages in said cylinder men ber communicating with said corresponding passages in said heads, and sealing means arranged in the space between said heads and said head chambers for preventing mix ing of inlet and e'xhaustgases.

5. A multi-cylinder internal combustion engine having a cylinder member provided with cylinders and substantially cylindrical head chambers arranged above said cylinders, cylinder heads arranged in said head chambers and having cylindrical outer walls spaced from the walls of said head chambers, communicating inlet and exhaust passages in said cylinder heads and said cylinder member, and substantially upright sealing members arranged in the space between the cylindrical walls of said cylinder heads and said head chambers to prevent the How of gases .in said space.

6. A multi-cylinder internal combustion engine having a cylinder member provided with a plurality of cylinders and having a cylindrical head chamber arranged above each cylinder, a cylinder head arranged in in the spacebetween the cylindrical walls of I the heads and head chambers and connecting said annular sealing means to prevent the passage 01' the gases in said annular space.

T. A multi-cylinder internal combustion engine having a cylinder member provided with a plurality of cylinders and having a cylindrical head chamber arranged above each cylinder, a cylinder head arranged in each or said head chambers and having cylindrical outer walls spaced from the cylind'ical wall of the head chambers, annular sealing means near the upper and. lower ends of said cylinder heads to form tight joints with said head chambers, communicating inlet and exhaust passages in said cylinder heads and saidcylin der mem her, and substantially upright sealing plates made or spring metal and arranged'in the space between said head and said head chamber and spaced between said annular sealing means, the intermediate portions of said plates being yieldingly pressed against said cylinder head and the edge portions bearing against the wall of said head chamber. I V i i i 8. A multi-cylinder internal combustion engine having a cylinder member provided with a plurality of cylinders and having a cylindrical head chamber arranged above each cylinder, a cylinder head arranged in each of said head chambers andincluding a cylindrical wall connected at a distance from the bottom thereof by a transverse wall, valves arranged in said transverse wall, spark plugs secured to said cylindrical wall below said transverse Wall, and cavities in said cylinder member through which said spark plugs extend.

9. A multi-cylinder internal combustion engine having a cylinder member provided with head chambers above each of the cylinders, a cylinder head arranged in each of said head chambers and including a substantially cylindrical wall and a transverse Wall connecting said cylindrica wall at a distance above the lower edge thereof to form a combustio n chamber, valves in said transverse wall, spark plugs arranged in said cylindrical wall below said transverse wall, sealing means between said cylinder member and said cylinder heads arranged above and below said spark plugs, and cavities in said cyl inder member through which said spark plugs extend to said cylinder heada' 10. A multi-cylinder internal combustion engine having a cylinder member provided with head chambers above each of the cylinders, a cylinder head arranged in each of said head chambers and including a substantially cylindrical wall and a transverse wall connecting said cylindrical wall at a distance above the lower edge thereof to form a coinbustion chamber, valves in said transverse Wall, spark plugs arranged in said cylindrical wall below said transverse wall, sealing means between said cylinder member and said cylinder heads arranged above and below said spark plugs, cavities in said cylinder member through which said spark plugs extend to said cylinder heads, communicating inletand exhaust passages in said heads and said cylinder member, the cylindrical walls of said heads and said head chambers being spaced apart, and upright sealing plates ar ranged in the spaces between said cylindrical walls to prevent the passage of gases in said space.

11'. A multi-cylinder internal combustion engine having individual removable cylinder heads provided with spaces for the circulation of a'cooling liquid, a supply passage extending lengthwise of said engine below said heads, and siphon pipes extending upwardly from said supply passage and downwardly into said heads adjacent to the lower portions of the circulating spaces therein and in which liquid flows from said passage to said heads, and means near the upper portions of said spaces in said heads for discharging cooling liquid therefrom, whereby said siphon tubes will draw liquid from said heads into saidsupply passage when engine cooling liquid is being withdrawn from said supply passages.

12. A multi-cylinder internal combustion engine including a cylinder member, individual removable heads mounted on said cylinder member, said cylinder member including jackets for the circulation of cooling liquid, a supply passage for cooling liquid formed on said cylinder member, siphon pipes extending upwardly from said supply passage and downwardly into said heads adj acent to the lower portions of the water circulating spaces in said heads, the portions of said siphon pipes terminating in said supply passage being arranged at a lower level than the portions thereof terminating in said cylinder heads, and discharge pipes leading from the upper portions of the cooling spaces of said cylinder heads to the water jackets of said cylinder member.

13. A multi-cylinder internal combustion engine including a cylinder member .provided with a plurality of cylinders and with cylinder head chambers arranged above said cylinders and having a jacket for cooling liquid extending around said cylinders and cylinder head chambers, cylinder heads in said cylinder head chambers and provided with spaces for the circulation of cooling liquid, a passage on said cylinder member for supplying cooling liquid, siphon pipes extending upwardly from said supply passage through the jackets of said cylinder head chambers and then downwardly into the lower portions of the circulating spaces of said cylinder heads, and pipes leading from the upper portions of said cooling liquid spaces of said cylinder heads and terminating in the jackets of said cylinder member.

ELl/VOOD T. LARKIN. 

